Hi Moni and welcome! You can use several different types of stamps for soaps, not just ones specifically "designed" for soap. BB offers a huge line of both rubber and resin stamps, and also a video on soapqueen about how to use each kind and what soaps they are best for, here:
You can use a number of different types of scrapbooking stamps on your soaps as well but will get different results depending on the hardness of your soap, the detail of the stamps and things like that.
My favorite are the hard resin stamps that are actually designed for soap. I've bought a couple from Etsy for very cheap, but most are shipped from China and will take a while to get to you. I just ordered my first resin stamp from BB (I've used their rubber ones on MP and have a local soaping friend who uses the same one on his CP goat's milk soaps) and I'm really excited to give it a try.
(They look like this)